1. Field of the Invention
The present invention pertains to the field of hangars for ventilation ducts and particularly for fiberglass ventilation ducts.
2. Prior Art
There are a number of hangars for pipes, ventilation ducts and other such structures that include means to connect a duct to walls, ceilings, joists or other part of the structural surrounding. Some of these devices employ pointed ends which can be driven into joists or other support members. For example, U.S. Pat. Nos. 2,291,148, which discloses a pipe hangar having a U-shape to straddle a pipe and a seat on which a pipe rests, and 2,641,428, which also discloses a pipe hangar having U-shape to straddle a pipe and rollers on which the pipe rests. In addition, the devices of the patents provide load bearing surfaces for the supported piping or ductwork. Ducts frequently are supported by straps attached to floor joists or other support means at opposite sides of the ducts and passed beneath the ducts.
Often many duct supporting hangars are used in even small ventilation or heating systems. Ease of installation and low cost are of paramount concern necessary to minimize installation costs of a duct system. For the same reason, the hangars must be of light weight and must be of low cost.
Fiberglass ventilation ducts have also been developed as a means of reducing the weight of ducts used. With the development of the fiberglass ducts a need for hangars suitable for use with such ducts has developed. None of the devices heretofore known are sufficiently low in weight and cost to be completely satisfactory for use in fiberglass duct support. Furthermore, the use of fiberglass ducts allow for ease and speed of installation if proper hangars are used. None of the devices known to the prior art are specifically adaptable for use with fiberglass duct work. While other hangars for pipes and ducts have been proposed, as for example in U.S. Pat. Nos. 2,286,118 (Sleeth) and 2,304,973 (Vecchiola), none are easily and quickly installed and will readily stabilize fiberglass ducts.